Hunch Looked, found nothing AD 850

Each Maya city fell silent during a local dry spell

Tested 25 October 2026. Pre-set test: the decade ending at each of the 89 last monuments was no drier than chance in the Yok Balum record (p 0.46). Exploratory, 20-year periods: the number of cities ending tracks dryness (r +0.58, p 0.06) only because of 780-799, and the share of still-active cities ending runs the wrong way (r -0.41). The peak of shutdowns (780-799) came before Cariaco's dry century (820-919), and in the cave record the last cities ended in wet years. Both records agree the collapse fell in a drier era that ended about 920 (already published); neither ties particular cities to particular dry spells. Dating caveats: monuments on fixed calendar dates, stalagmite age errors of a few years.

How it connects

This hunch is about Did drought bring down the Classic Maya cities (about 750 to 910)?

This hunch we read it in Ebert, Prufer, Macri, Winterhalder and Kennett 2014, Terminal Long Count dates and the disintegration of Classic Period Maya polities, Ancient Mesoamerica 25:337 (Table 1: last dated monument at 89 sites). Saved as maya/terminal_dates.csv

This hunch we read it in Kennett et al. 2012, Development and disintegration of Maya political systems in response to climate change, Science 338:788; Yok Balum YOK-I stalagmite and tuned Cariaco titanium, NOAA

This hunch is argued against by Yok Balum and Cariaco: a drier era overall, but they disagree on which decades no city-by-city alignment with dry spells

This hunch came from this step Tested the Maya city shutdowns against two drought records